Agrotain urease inhibitor keeps urea fresh

Mar 30, 2001

With prohibitive fertilizer and fuel prices, it follows reason that more growers are looking at no-till farming. A product now being introduced into the South may make no-tilling even more of a temptation.

It doesn't take too much of an imagination for a Delta farmer to come up with this scenario: it's early in the season and you're wanting to plant. Urea has been surface-applied, but the rain forecasts haven't come through. Time is wasting away, along with the urea's potency.

But all isn't lost. Between bouts of swearing at the weatherman and rain-dancing, farmers may consider Agrotain. Already used by many Midwest growers, Agrotain stops nitrogen volatilization for up to two weeks — long enough for those rain showers to arrive, says IMC-Agrico.

“Nitrogen loss is a major concern for growers, and should be, because it means reduced yields, higher costs for extra nitrogen applications and fuel, along with additional time in the field,” says IMC Global manager of product development Allen Sutton.

Volatilization of urea actually occurs when nitrogen in urea becomes a gas. In less than three days, 30 percent or more of urea's nitrogen value can be lost through the action of urease. Urease, a soil-microbe produced enzyme, is the real culprit in the volatilization process. Urease quickens urea's reaction to air and soil moisture.

Agrotain stops urease by using a synthesized molecule called NBPT. Discovered in the mid-1980s, the molecule's abilities were known but not commercialized by the original finders. IMC-Agrico saw the product's potential.

Looking like wet fiberglass, the active ingredient of Agrotain was at first a bit tricky to manufacture. Since then, however, a safe, easy-to-handle liquid concentrate has been developed. Users and environment are both safe through use of the product which degrades into typical fertilizer elements (phosphorus and sulfur, along with nitrogen).

Agrotain mixes well with UAN solutions and impregnates easily onto urea for mixing. IMC-Agrico claims it has tested the product in different fertilizer-blending equipment and found it's compatible with major corn herbicides.

Proponents of the product (costing about $8 per acre) — particularly on reduced-till land — aren't hard to find.

“If you use reduced tillage and have lots of crop residue, no rain is in sight, and you want to get your corn planted, I'd definitely think about this product as a nitrogen management option,” says University of Illinois soil scientist Bob Hoeft.

Tested over many years on corn (although it can be used on all crops) in around 20 states and 20 universities, Agrotain has performed consistently well. In 281 tests where rain was a no-show for at least three days, Agrotain-treated land yielded an average bump of just over 14 bushels per acre.

However, “we're not positioning it as a yield-enhancer,” says Sutton. “We're saying if you've got a situation where that fertilizer may sit on top of the soil for a few days, here's a product to prevent loss. It will not do anything for fertilizer already in the soil.

“No-till corn is where it really shines. But it's also an excellent product for wheat, pasture and forage crops.”

And Agrotain performs consistently. “Every year that we had potential for urea nitrogen loss, this product did its job,” says Lloyd Murdock, University of Kentucky Extension soil scientist.